Travel-Associated Dengue Cases-United States, 2010-2021

Dengue, the leading cause of arboviral disease worldwide, can be fatal without appropriate treatment. Among 7,528 con-firmed or probable travel-associated U.S. dengue cases reported during 2010-2021, one in five (1,474, 20%) was reported in 2019. This is 168% higher than the annual average number of cases reported during 2010-2018 and 2020-2021 (approximately 550 per year) and 61% higher than the 913 cases reported in 2016, the second highest year on record. The number of cases as a fraction of air traffic volume to international destinations outside North America or Europe was also highest in 2019, with 41.9 cases per million trips, compared with 21.0 per million in other years during 2010-2021. This report compares the number and characteristics of travel-associated dengue cases reported to national surveillance in the United States in 2019 with cases reported during 2010-2018 and 2020-2021. Areas with conditions suitable for dengue transmission as well as the population at risk for dengue are expected to increase, placing U.S. travelers at higher risk for infection. Health care providers should be aware that dengue is a common cause of fever in the returning traveler and be familiar with its signs and symptoms, testing, and management. Dengue vaccines are not currently recommended for U.S. travelers; therefore, persons should review areas of dengue risk and follow guidance for preventing mosquito bites.

Automated summary

Among travel-associated U.S. dengue cases reported during 2010-2021, the highest number occurred in 2019, with a 61% increase compared to the second highest year on record. The number of cases per million trips outside North America or Europe was also highest in 2019, indicating a higher risk for infection. Health care providers should be familiar with dengue symptoms and treatment, while travelers should follow mosquito bite prevention guidance as dengue vaccines are not recommended.